Black Fitbit Flex Wireless Activity + Sleep Tracker Wristband

This is the most popular activity tracker sofar.
Track step, distance, calories burned, active minutes, and how long and well you sleep.
Wakes you (and not your partner) with a silent wake alarm.
Comes with small and large wristbands
Data syncing goes wirelessly and automatically to your computer and over 120 leading smartphones.

Disadvantage:
Data collected can't be seen on the wristband.
You have to sync your data to your phone or computer.
This tracker might be a bit less accurate than for example the Fitbit One.

Thin straps featuring black diamond colored UP2 activity and sleep tracker.
This tracker uses an accelerometer and algorithms to track and quantify your activities.
You need the fitness app to use on your smartphone.
Your activity and sleep data will be synchronized wirelessly.
You can use the Smart Coach for personal guidance.
With the Smart Alarm you can silently wake up at the optimal time in your sleep cycle.

Wireless Activity & Fitness Tracker OUMAX T3 with OLED Dsiplay

Dimensions: 5.5 x 4.3 x 1.2 inches and weighs 7 ounces.
You can track your steps, distance, calories burned, activity time.
You can get waked up by the silent alarm and monitor how long and well you slept.
This tracker can wireless synchronize your tracker data via Bluetooth to compatible devices such as iOS 9.0 equipped iPhones, iPads. and Android 4.3 and higher equipped Android phones.
There are also options for connecting a remote camera incoming calls.
Comes with replacement colored bands (pink and blue), and manual.

Wireless Activity and Sleep Tracker AVANTEK

Specially designed for iOS users, is made from TPE material and is water resistant.
Works with the "AVANTEK Sport" app which is suitable for iOS 7.0+ devices.
Features steps display, exercise timer, alarm, sleep monior.